Various components are designed and manufactured to have thin walls. Thin wall technology is increasingly used in components that have application in the transportation industry where it is desired to save weight. Thin wall manufacturing is also used in order to minimize material consumption, and the associated cost, during manufacturing. Thin wall design, described generally, means designing a component with a wall thickness set at or near a minimum needed thickness consistent with the strength requirements for the part. For example, fluid pump housings used in aircraft applications may be complex aluminum castings with thin wall technology. Housing walls in such a component may have a thickness of between about 0.050 to about 0.070 inches. Other structures presently used in aircraft that may have a thin wall design include fuel control housings, lube modules, oil pump housings, and pneumatic valve bodies.
However, the thin wall construction technique is creating difficulties when the time comes to repair the component. After a period of service, a component surface may experience wear or erosion. Fluid pumps, for example, may encounter fluid erosion at surface areas of the component along fluid paths. Mechanical erosion also occurs on those surfaces of a component that experience metal to metal contact. In order to repair surfaces suffering wear, erosion, or scratching, it is generally necessary to machine away a portion of the worn surface. However, if the worn surface is part of a thin wall structure, there is little to no tolerance for machining away material. Machining away material from a worn surface may so weaken the structure that the part could not meet basic strength specifications. However, scrapping the part is often not an attractive alternative. Aluminum castings, such as those described above, can be expensive to replace. Moreover, when a component becomes damaged, it may be that only the wear surface needs to be repaired, while the remainder of the structure is still usable. Thus, it would be desired to find an acceptable repair technique if possible.
Some repair strategies, such as various welding processes, add material to a worn component. Welding, however, is often not well suited to those components having thin wall construction. Welding typically involves heating a component surface to a high temperature sufficient to melt both the surface substrate and an additive material. This high heat can damage the component being repaired. A thin wall structure is particularly subject to warpage during a high heating process such as may be encountered during welding. Moreover, aluminum parts, often found in aviation applications, are also susceptible to heat induced warpage. Thus, it would be desired to identify a repair technique that avoids the potentially negative effects of high heat.
Hence there is an ongoing need to provide improved methods for repairing damaged components with thin walls. It would be desirable to develop repair methods that are simple, inexpensive, and restore the component to a level of performance at least equal to, or preferably, superior to that of the original construction. Finally, it is desired that the repair method allow the assembly to be quickly returned to service. The present invention addresses one or more of these needs.